Reduced circulating osteopontin levels are associated with elevated blood pressure and vascular endothelial-related alterations in children with obesity

Childhood obesity is associated with metabolic abnormalities and elevated blood pressure, increasing the risk of early cardiovascular complications. Osteopontin (OPN), a multifunctional protein involved in inflammation and vascular homeostasis, has been implicated in cardiometabolic disorders. However, its association with blood pressure alterations in children with obesity remains unclear. This study aimed to investigate the associations of serum OPN levels with metabolic parameters, vascular endothelial-related markers, and elevated blood pressure in children with obesity. A total of 106 children were enrolled, including 61 children with obesity and 45 non-obese controls. Anthropometric parameters, metabolic profiles, blood pressure, circulating OPN and adiponectin (ADPN) levels, as well as vascular endothelial-related markers were assessed. Correlation analyses were performed to evaluate associations between OPN and clinical variables. Multivariable linear regression analysis was conducted to evaluate the association between OPN and systolic blood pressure (SBP) in children with obesity. Receiver operating characteristic (ROC) curve analysis was performed to assess the performance of OPN-containing models for identifying elevated blood pressure. Children with obesity showed higher BMI, blood pressure, triglycerides, total cholesterol, and vascular cell adhesion molecule-1 (VCAM-1), whereas circulating OPN, adiponectin (ADPN), Wnt family member 5 A (WNT5A), and endothelial cell-specific molecule 1 (ESM1) levels were lower compared with controls (all p < 0.05). In addition, OPN levels were inversely correlated with BMI (r = 0.704, p < 0.001), SBP (r = −0.557, p < 0.001), DBP (r = −0.279, p = 0.013), and VCAM-1 (r = −0.355, p = 0.001), but positively correlated with WNT5A and ESM1 (all p < 0.05). After adjustment for age, sex, and pubertal status, OPN was associated with lower SBP (β = −0.452, 95% CI: −4.30 to −0.74, p = 0.007). The addition of OPN to the basic clinical model improved its ability to identify elevated blood pressure, with the AUC increasing from 0.756 to 0.806. Circulating OPN levels are inversely associated with obesity, blood pressure, and are correlated with vascular endothelial-related markers in children. The findings suggest that serum OPN may serve as a potential biomarker of cardiometabolic risk in children with obesity.